Pd(II)-Catalyzed C4-Selective Alkynylation of Indoles by a Transient Directing Group

作者：Ze-Xuan Zhang, Bing Zhang, Meng Yuan, Pengfei Zhao, Chao‐Shan Da · 发表于：Organic Letters · 年份：2024 · DOI：10.1021/acs.orglett.4c01970 · 被引用次数：10 · 研究领域：Catalytic C–H Functionalization Methods、Catalytic Cross-Coupling Reactions、Synthesis of Indole Derivatives

With alanine as a transient directing group, Pd-catalyzed regioselective alkynylation at the indole C4-position was successfully established in a good yield. The total synthesis of the PAF antagonist demonstrated the synthetic utility of this protocol. The regioselectivity was explicitly proven by the prepared C4-selective palladacycle intermediate in the catalytic process and the DFT calculation of the energy barriers of C4- and C2-site-selective C-H activation of indole.